The cored hulls have not been an issue with the Tartan 37. I know it's not the ideal hull to have if it does get moisture, but the coring on the T-37 is only in the large panel areas and not too close to the centerline where any impact would likely be. The outer skin of fiberglass is quite thick and then they laid the coring, then woven roving over that. Its a stiff hull with no flex. All of the bulkheads are tabbed neatly.
The downside for the T-37 is that the storage for fuel/water/propane is a little limited. 50 fuel, 90 water, and propane was usually added retro with a 13 # tank.
She sails with the fingertips and is nice to look at.